There are many procedures described for the treatment of acromioclavicular separation. Eleven cases were operated on by technique of Weaver and Dunn method and ten cases by modified Phemister method and four cases by Dewar and Barrington method, and one cases by Mumford method, Dept. of Orthopaedic Surgery, Capital Armed Forces General Hospital from March 1986 to March 1989. The following results were obtained. l. All patients were male and the peak incidence was in 3rd decade(77%). 2. The most common causes of the injuries were athletic accidents and followed by traffic accidents. 3. Twenty three patients were grade III by Allman's classification and grade II in three cases. 4. Clinical results were good in 19 cases(73.1%), fair in 5 cases(19.2%) and poor in 2 cases(7.7%). 5. The operative procedures in grade III may be good treatment of acromioclavicular separation.